Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-10T16:20:47.544Z Has data issue: false hasContentIssue false

Feeding mulberry leaves to fattening rabbits: effects on growth, carcass characteristics and meat quality

Published online by Cambridge University Press:  09 March 2007

M. Martínez
Affiliation:
Universidad Tecnológica del Chocó, Departamento Ingeniería Agroforestal, Barrio Medrano, Quibdó, Colombia
W. Motta
Affiliation:
Universidade Federal Minas Gerais, Escola de Veterinaria. Departamento Zootecnia. Avenida Antonio Carlos, 6627, CP 567 Belo Horizonte, Brasil
C. Cervera
Affiliation:
Universidad Politécnica de Valencia, Departamento de Ciencia Animal, Camino de Vera s/n 46022 Valencia, Spain
M. Pla*
Affiliation:
Universidad Politécnica de Valencia, Departamento de Ciencia Animal, Camino de Vera s/n 46022 Valencia, Spain
*
E-mail: mpla@dca.upv.es
Get access

Abstract

One hundred and thirty-two young rabbits were divided into two groups at weaning and given ad libitum a control diet (C), or an experimental diet (M) in which lucerne hay was substituted by mulberry leaves in order to examine their effects on fattening rabbit performance, carcass characteristics and meat quality.

Digestibility coefficients of dry matter (DM), crude protein and gross energy were similar in both groups but digestibility of crude fibre in the experimental diet was higher in line with a lower food intake in this group of animals, while ether extract digestibility of mulberry leaves was very low.

Food conversion ratio was similar in the two groups (3.1 g DM per g gain) but rabbits given the experimental diet had lower food intake (102 v. 144 g/day) and impaired live-weight gain. The rate of mortality was similar in the two groups. The substitution of lucerne with mulberry in the diet may have induced a higher retention time of digesta, as seems to be indicated by a higher weight of digestive tract contents recorded at slaughter (proportionately 0.32 more) in mulberry group. Live weight at slaughter of animals in control group was higher (2680 v. 2211 g) and also skin weight was proportionately 0.5 higher and its carcasses were proportionately 0.41 heavier than those of animals in experimental group (dressing yield 587 v. 503 g/kg). At constant carcass weight, the carcasses of rabbits of the mulberry group were longer than the lucerne group, but lumbar circumference tended also to be higher (P = 0.09) and no differences were found in the length: circumference ratio. No differences were found in the weights of kidneys or thoracic viscera, but livers of rabbits of the lucerne group were heavier (proportionately 0.3 heavier). The more remarkable difference was that carcasses of rabbits given the experimental diet had markedly less fat in scapular (5.8 v. 10.0 g) and perirenal fat (9.0 v. 22.3 g) deposits.

No differences in cooking losses or water-holding capacity of the meat were found and also the colour was similar, but the b* parameter was a little lower for meat of the M group rabbits.

The proportion of protein in the meat was the same for rabbits of the two groups, but rabbits given the experimental diet which had leaner carcasses also had leaner meat (19 v. 37 g lipids per kg meat) and a little more moisture (755 v. 736 g/kg meat). Intra and intermuscular fat of hindleg meat from rabbits of group M was less saturated and more unsaturated than that of the conventional rabbits mainly due to its higher proportion of polyunsaturated fatty acids, ω6 (37·3 v. 29·1 g/100 g lipids) and ω3 (3·4 v. 2·2 g/ 100 g lipids). Polyunsaturated: saturated ratio was higher in the mulberry group than in the lucerne group (1·15 v. 0·85) indicating a more desirable value in rabbits given the experimental diet, so meat of these rabbits could be considered preferable for human nutrition from this point of view.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alasnier, C., Viau, M. and Gandermer, G. 1994. Lipid composition of two rabbit muscles of opposite metabolic type. Proceedings of the 40th international congress of meat science and technology, The Hague, SIV-B. 44/1.Google Scholar
Baselga, M. 2002. Rabbit genetic resources in Mediterranean countries: Line A, Line V, Line H and Line R. Options Méditerranéennes 38: 221262.Google Scholar
Blasco, A. and Ouhayoun, J. 1996. Harmonization of criteria and terminology in rabbit meat research: revised proposal. World Rabbit Science 4: 9399.Google Scholar
Casoli, C., Duranti, E., Damiani, P. and Rongoni, V. 1986. Composizione chimica e valore nutritivo di foglie di Morus alba. Zootecnica e Nutrizione Animale 12: 4754.Google Scholar
Commission Internationale de l'Éclairage. 1976. Colorimetry. Bureau Central de la CIE, Vienna, publication no. 15.Google Scholar
Dalle Zotte, A. 2002. Perception of rabbit meat quality and major factors in. uencing the rabbit carcass and meat quality. Livestock Production Science 75: 1132.CrossRefGoogle Scholar
Deltoro, J. and López, A. M. 1986. Development of commercial characteristics of rabbit carcasses during growth. Livestock Production Science 15: 271283.Google Scholar
Department of Health and Social Security UK. 1984. Diet and cardiovascular diseases. DHSS report on health and social subjects, no. 28. Her Majesty's Stationery Office, London.Google Scholar
Deshmukh, S. V., Pathak, N. N., Takalikar, D. A. and Digraskar, S. U. 1993. Nutritional effect of mulberry (Morus alba) leaves as sole ration of adults rabbits. World Rabbit Science 1: 6769.Google Scholar
European Group of Rabbit Nutrition. 2001. Technical note: attempts to harmonize chemical analyses of feeds and faeces for rabbit feed evaluation. World Rabbit Science 9: 5764.Google Scholar
Enser, M., Hallet, K., Hewett, B., Fursey, G. A. J. and Wood, J. D. 1996. Fatty acid content and composition of English beef, lamb and pig at retail. Meat Science 42: 443456.CrossRefGoogle Scholar
Enser, M., Hallet, K. G., Hewett, B., Fursey, G. A. J., Wood, J. D. and Harrington, G. 1998. Fatty acids content and composition of UK beef and lamb muscle in relation to production system and implications for human nutrition. Meat Science 49: 329341.Google Scholar
Fernández-Carmona, J., Cervera, C., Moya, J. and Pascual, J. J. 2002. Feeding ryegrass hay to growing rabbits. World Rabbit Science 9: 9599.Google Scholar
Fernández-Carmona, J., Cervera, C., Sabater, C. and Blas, E. 1995. Effect of diet composition on the production of rabbit breeding does housed in a traditional building and at 30°C. Animal Feed Science and Technology 52: 289297.CrossRefGoogle Scholar
Hamm, R. 1986. Functional properties of the myo. brillar system and their measurements. In Muscle as food (ed. Betchel, P. J.), pp. 135199. Academic Press Inc., Orlando, USA.Google Scholar
Lara y Lara, P. E., Sanginés, G. R. and Dzib, M. R. 1998. Utilización de hojas de morera (Morus alba) en la producción de carne de conejo. Memorias del IX Congreso Nacional de Investigación y Desarrollo Tecnológico Agropecuario. ITA 2, Condal, Yucatán.Google Scholar
Machii, H. 1989. Varietal differences of nitrogen and amino acid contents in mulberry leaves. Acta Sericologica et Entomologica (Japan) 1: 5161.Google Scholar
Ouhayoun, J. 1992. Rabbit meat: characteristics and qualitative variability. Cuni-Sciences 7: 115.Google Scholar
Ouhayoun, J. 1998. Influence of the diet on rabbit meat quality. In The nutrition of the rabbit (ed. de Blas, C. and Wiseman, J.), pp. 177195. CAB International, Wallingford.Google Scholar
Perez, J. M., Lebas, F., Gidenne, T., Maertens, L., Xiccato, G., Parigi-Bini, R., Dalle-Zotte, A., Cossu, M. E., Carazzolo, A., Villamide, M. J., Carabaño, R., Fraga, M. J., Ramos, M. A., Cervera, C., Blas, E., Fernández-Carmona, J., Falcao e Cunha, L. and Bengala Freire, J. 1995. European reference method for in vivo determination of diet digestibility in rabbits. World Rabbit Science 3: 4143.Google Scholar
Pla, M., Pascual, M. and Ariño, B. 2004. Protein, fat and moisture content of retail cuts of rabbit meat evaluated with the NIRS methodology. World Rabbit Science 12: 149158.Google Scholar
Sanchez, M. D. 2000. Mulberry: a high quality forage available almost worldwide! World Animal Review volume 93. FAO, Rome.Google Scholar
Singh, B., Goel, C. G. and Negi, S. S. 1984. Effect of supplementing mulberry (Morus alba) leaves ad libitum to concentrate diets of Angora rabbits on wool production. Journal of Applied Rabbit Research 7: 156160.Google Scholar
Statistical Analysis Systems Institute. 1990. User's guide: statistics. Statistical Analysis Systems Institute Inc., Cary, NC.Google Scholar
Villamide, M. J., Maertens, L., Blas de, C. and Perez, J. M. 1998. Feed evaluation. In The nutrition of the rabbit (ed. de Blas, C. and Wiseman, J.), pp. 89101. CAB International, Wallingford.Google Scholar